A fire-resistant and heat-insulating silicone potting compound with fire extinguishing function

Abstract

This invention relates to the field of organosilicon material application technology, specifically a heat-insulating and fire-retardant organosilicon potting compound for lithium battery encapsulation protection, which also has fire-extinguishing functions. It is composed of silicone oil, hydroxyl silicone oil, hexamethyldisilazane, silane coupling agent, silica reinforcing agent, crosslinking agent, and other components in a specific weight ratio. The components work synergistically. This potting compound is a lightweight gel with a thermal conductivity ≤0.1W / m・K, effectively providing heat insulation. When the temperature reaches 135℃~180℃, it releases fire-extinguishing gas to cool and extinguish the fire. Upon contact with fire, it forms a honeycomb ceramic structure, preventing the spread of flames. It can be used for heat insulation and fire protection between battery cells and modules, as well as between modules and the casing, meeting the GB38031-2025 safety requirements for power batteries. It solves the problem of fires and explosions caused by battery thermal runaway, improving battery safety performance in scenarios such as new energy vehicles and energy storage power stations.

Description

Technical Field

[0001] This invention relates to the field of organosilicon material application technology, specifically to a fireproof and heat-insulating organosilicon potting compound with fire extinguishing function. Background Technology

[0002] Battery thermal runaway protection is crucial for ensuring battery safety, especially in new energy vehicles and energy storage power stations. This is primarily because lithium-ion batteries are prone to a chain reaction of exothermic reactions under conditions such as overheating, overcharging, and short circuits, leading to thermal runaway and even serious accidents such as fires and explosions. The government has also introduced various regulations to ensure battery safety. GB38031-2025, considered the strictest power battery regulation in history, will be implemented on July 1, 2026, requiring that batteries not catch fire or explode after thermal runaway.

[0003] Battery thermal runaway protection is a systematic project, and the thermal insulation and fireproof structural protection between cells, between modules, and between modules and the battery pack casing is an important part.

[0004] Among them, patent CN119371930A provides a low-density ceramicizable potting compound to provide flame retardant, heat insulation and fireproof functions between battery cells.

[0005] Patent CN105482465B provides a low-stress potting compound that can effectively control the technical problem of the entire battery pack exploding and burning after a single battery explodes.

[0006] Patent CN109439272A mentions using thermally conductive potting compound to provide heat dissipation protection for the battery.

[0007] The above patents all use organosilicon-modified formulations to provide heat insulation or heat conduction, flame retardancy, and fire prevention functions to protect against battery thermal runaway, but they do not have the function of actively absorbing heat or extinguishing fires. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this invention provides a fire-resistant and heat-insulating silicone potting compound with fire-extinguishing function.

[0009] To achieve the above objectives, the present invention provides the following technical solution: a fire-retardant and heat-insulating silicone potting compound with fire-extinguishing function, comprising the following components in parts by weight: Silicone oil - 100 parts; Hydroxy silicone oil - 0.5 to 10 parts; Hexamethyldisilazane - 0.5 to 5 parts; Silane coupling agent - 0.5 to 5 parts; Silica reinforcing agent - 0 to 100 parts; Crosslinking agent - 0.5~30 parts; Crosslinking accelerator - 0.5 to 10 parts; Crosslinking inhibitor - 0.5~10 parts; Flame retardant - 0 to 50 parts; Synergistic flame retardant - 0~10 parts Extinguishing agent - 0 to 50 parts.

[0010] Furthermore, an improvement of the present invention is that the silicone oil is a mixture of one or more methyl vinyl silicone oils with a viscosity range of 50 to 5000 cp and a vinyl molar percentage of 0.04% to 5%.

[0011] Furthermore, an improvement of the present invention is that the hydroxyl silicone oil is a hydroxyl-terminated polydimethylsiloxane with a viscosity of 30-35 mm² / s at 25°C, a hydroxyl content of 8-10%, and a pH value of 6.5-7.5.

[0012] Furthermore, an improvement of the present invention is that the silane coupling agent is one or more of dimethyldimethoxysilane, vinyltrimethoxysilane, and vinyltriethoxysilane.

[0013] Furthermore, an improvement of the present invention is that the silica reinforcing agent is one or more fumed silicas with a specific surface area of ​​150-380 m² / g and an average particle size of 7-40 nm.

[0014] Furthermore, an improvement of the present invention is that the crosslinking agent is one or more hydrogen-containing silicone oils with a hydrogen content ranging from 0.1% to 1.2%.

[0015] Furthermore, an improvement of the present invention is that the catalyst is a mixture, the main components of which are 5000ppm castor platinum complex: 1-ethynyl-1-cyclohexanol: methyl silicone oil: mixed in a ratio of 4:1:50.

[0016] Furthermore, an improvement of the present invention is that the flame retardant is one or a mixture of several of the following: aluminum hydroxide, magnesium hydroxide, zinc borate, calcium carbonate, molten glass powder, vacuum glass powder, clay powder, wollastonite fiber, and mica powder.

[0017] Furthermore, an improvement of the present invention is that the synergistic flame retardant is one or a mixture of several of cerium oxide, iron oxide, titanium oxide, melamine, and melamine cyanurate.

[0018] Furthermore, an improvement of the present invention is that the extinguishing agent employs extinguishing microcapsules, which have a core-shell structure and an activation temperature of 135℃~180℃. The core extinguishing substance is one or a mixture of several of the following: perfluorohexanone / perfluorotriethylamine and its homologues, inorganic alkali metal potassium salts / organic potassium salts, and gaseous extinguishing agents (such as heptafluoropropane); the capsule shell material is one or a mixture of several of the following: chitosan / sodium alginate, acrylic resin, polyamide resin, and polymers of methyl methacrylate and N,N-dimethylacrylamide.

[0019] Compared with the prior art, the present invention provides a fireproof and heat-insulating silicone potting compound with fire extinguishing function, which has the following beneficial effects: 1. This potting compound is a lightweight gel material, which can effectively reduce the weight of the adhesive used; 2. This potting compound has excellent thermal insulation properties, with a thermal conductivity that can be controlled below 0.1 W / mk. It can effectively isolate the heat generated by thermal runaway of a single cell or multiple cells, without endangering the surrounding batteries. 3. When the temperature exceeds the range of 135℃~180℃, the potting compound can release fire extinguishing gases, which can actively cool down and extinguish the fire. 4. The gel can form a honeycomb ceramic structure in a flame, which can further isolate the spread of flame and heat, especially protecting the battery casing and further enhancing the safety of the occupant compartment. Detailed Implementation

[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0021] The present invention provides a fire-retardant and heat-insulating silicone potting compound with fire-extinguishing function, comprising the following components in parts by weight: Silicone oil - 100 parts; Hydroxy silicone oil - 0.5 to 10 parts; Hexamethyldisilazane - 0.5 to 5 parts; Silane coupling agent - 0.5 to 5 parts; Silica reinforcing agent - 0 to 100 parts; Crosslinking agent - 0.5~30 parts; Crosslinking accelerator - 0.5 to 10 parts; Crosslinking inhibitor - 0.5~10 parts; Flame retardant - 0 to 50 parts; Synergistic flame retardant - 0~10 parts Extinguishing agent - 0 to 50 parts.

[0022] Furthermore, an improvement of the present invention is that the silicone oil is a mixture of one or more methyl vinyl silicone oils with a viscosity range of 50 to 5000 cp and a vinyl molar percentage of 0.04% to 5%.

[0023] Furthermore, an improvement of the present invention is that the hydroxyl silicone oil is a hydroxyl-terminated polydimethylsiloxane with a viscosity of 30-35 mm² / s at 25°C, a hydroxyl content of 8-10%, and a pH value of 6.5-7.5.

[0024] Furthermore, an improvement of the present invention is that the silane coupling agent is one or more of dimethyldimethoxysilane, vinyltrimethoxysilane, and vinyltriethoxysilane.

[0025] The fumed silica reinforcing agent is one or more types of fumed silica with a specific surface area of ​​150-380 m² / g and an average particle size of 7-40 nm.

[0026] The crosslinking agent is one or more hydrogen-containing silicone oils with a hydrogen content ranging from 0.1% to 1.2%.

[0027] The catalyst is a mixture, mainly composed of 5000ppm castor platinum complex, 1-ethynyl-1-cyclohexanol, and methyl silicone oil, mixed in a ratio of 4:1:50.

[0028] The flame retardant is one or a mixture of several of the following: aluminum hydroxide, magnesium hydroxide, zinc borate, calcium carbonate, molten glass powder, vacuum glass powder, clay powder, wollastonite fiber, and mica powder.

[0029] The synergistic flame retardant is one or a mixture of several of cerium oxide, iron oxide, titanium oxide, melamine, and melamine cyanurate.

[0030] The extinguishing agent is a fire-extinguishing microcapsule with a core-shell structure and a triggering temperature of 135℃~180℃. The core extinguishing substance is one or a mixture of several of the following: perfluorohexanone / perfluorotriethylamine and its homologues, inorganic alkali metal potassium salts / organic potassium salts, and gaseous extinguishing agents (such as heptafluoropropane); the capsule shell material is one or a mixture of several of the following: chitosan / sodium alginate, acrylic resin, polyamide resin, and a polymer of methyl methacrylate and N,N-dimethylacrylamide.

[0031] When in use, the adhesive is poured into the gaps between the lithium battery cells and modules and the connection with the casing. After curing, it forms a lightweight gel (density ≤1.2g / cm³), which also has the function of extinguishing fire and can effectively protect the battery under thermal runaway conditions.

[0032] 1. This potting compound is a lightweight gel material, which can effectively reduce the weight of the adhesive used; 2. This potting compound has excellent thermal insulation properties, with a thermal conductivity that can be controlled below 0.1 W / mk. It can effectively isolate the heat generated by thermal runaway of a single cell or multiple cells, without endangering the surrounding batteries. 3. When the temperature exceeds the range of 135℃~180℃, the potting compound can release fire extinguishing gases, which can actively cool down and extinguish the fire. 4. The gel can form a honeycomb ceramic structure in a flame, which can further isolate the spread of flame and heat, especially protecting the battery casing and further enhancing the safety of the occupant compartment.

[0033] In the description herein, it should be noted that relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0034] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention.

Claims

1. A fireproof and heat-insulating silicone potting sealant with fire extinguishing function, comprising, characterized by: The components include the following parts by weight: Silicone oil - 100 parts; Hydroxy silicone oil - 0.5 to 10 parts; Hexamethyldisilazane - 0.5 to 5 parts; Silane coupling agent - 0.5 to 5 parts; Silica reinforcing agent - 0 to 100 parts; Crosslinking agent - 0.5~30 parts; Crosslinking accelerator - 0.5 to 10 parts; Crosslinking inhibitor - 0.5~10 parts; Flame retardant - 0 to 50 parts; Synergistic flame retardant - 0~10 parts Extinguishing agent - 0 to 50 parts.

2. The fireproof and heat-insulating silicone potting sealant with fire extinguishing function according to claim 1, characterized in that: The silicone oil is a mixture of one or more methyl vinyl silicone oils with a viscosity range of 50 to 5000 cp and a vinyl molar percentage of 0.04% to 5%.

3. The fireproof and heat-insulating silicone potting compound with fire extinguishing function according to claim 2, characterized in that: The hydroxyl silicone oil used is a hydroxyl-terminated polydimethylsiloxane with a viscosity of 30-35 mm² / s at 25°C, a hydroxyl content of 8-10%, and a pH value of 6.5-7.

5.

4. The fireproof and heat-insulating silicone potting compound with fire extinguishing function according to claim 3, characterized in that: The silane coupling agent is one or more of dimethyldimethoxysilane, vinyltrimethoxysilane, and vinyltriethoxysilane.

5. The fireproof and heat-insulating silicone potting compound with fire extinguishing function according to claim 4, characterized in that: The fumed silica reinforcing agent is one or more types of fumed silica with a specific surface area of ​​150-380 m² / g and an average particle size of 7-40 nm.

6. The fireproof and heat-insulating silicone potting compound with fire extinguishing function according to claim 5, characterized in that: The crosslinking agent is one or more hydrogen-containing silicone oils with a hydrogen content ranging from 0.1% to 1.2%.

7. The fireproof and heat-insulating silicone potting compound with fire extinguishing function according to claim 6, characterized in that: The catalyst is a mixture, mainly composed of 5000ppm castor platinum complex, 1-ethynyl-1-cyclohexanol, and methyl silicone oil, mixed in a ratio of 4:1:

50.

8. The fire-retardant and heat-insulating silicone potting compound with fire-extinguishing function according to claim 7, characterized in that: The flame retardant is one or a mixture of several of the following: aluminum hydroxide, magnesium hydroxide, zinc borate, calcium carbonate, molten glass powder, vacuum glass powder, clay powder, wollastonite fiber, and mica powder.

9. The fire-retardant and heat-insulating silicone potting compound with fire-extinguishing function according to claim 8, characterized in that: The synergistic flame retardant is one or a mixture of several of cerium oxide, iron oxide, titanium oxide, melamine, and melamine cyanurate.

10. A fire-retardant and heat-insulating silicone potting compound with fire-extinguishing function according to claim 9, characterized in that: The extinguishing agent is a fire-extinguishing microcapsule with a core-shell structure and a triggering temperature of 135℃~180℃. The core extinguishing substance is one or a mixture of several of the following: perfluorohexanone / perfluorotriethylamine and its homologues, inorganic alkali metal potassium salts / organic potassium salts, and gaseous extinguishing agents (such as heptafluoropropane); the capsule shell material is one or a mixture of several of the following: chitosan / sodium alginate, acrylic resin, polyamide resin, and a polymer of methyl methacrylate and N,N-dimethylacrylamide.